How exercise and diet affect coronavirus risk

by MARY JO DILONARDO

How you move and how you eat could have an impact on how your body responds when faced with the coronavirus. Like so many other health complications, diet and exercise seem to affect the body’s ability to fight COVID-19 — the disease caused by the coronavirus — and its complications.

Exercise and COVID-19 complications

Regular exercise may help reduce the risk of acute respiratory distress syndrome (ARDS), a dangerous and potentially fatal condition caused by COVID-19, according to new research.

ARDS results when fluid builds up in in the tiny air sacs in the lungs, according to the Mayo Clinic. When this happens, lungs aren’t able to fill completely because of the fluid. That means less oxygen reaches the bloodstream, so organs don’t have enough oxygen to function.

Zhen Yan of the University of Virginia School of Medicine says medical research findings “strongly support” the possibility that exercise can prevent or at least reduce the severity of ARDS. Between 3% to 17% of all people with COVID-19 develop ARDS, according to the Centers for Disease Control and Prevention (CDC). An estimated 20% to 42% of hospitalized COVID-19 patients will develop ARDS. The range for patients admitted to intensive care is 67% to 85%.

According to earlier research, ARDS has a mortality rate as high as 45% for severe cases.

“All you hear now is either social distancing or ventilator, as if all we can do is either avoid exposure or rely on a ventilator to survive if we get infected,” Yan said in a statement. “The flip side of the story is that approximately 80% of confirmed COVID-19 patients have mild symptoms with no need of respiratory support. The question is, ‘Why?’ Our findings about an endogenous antioxidant enzyme provide important clues and have intrigued us to develop a novel therapeutic for ARDS caused by COVID-19.”

Yan, the director of the Center for Skeletal Muscle Research at UVA’s Robert M. Berne Cardiovascular Research Center, reviewed medical research of an antioxidant known as extracellular superoxide dismutase (EcSOD). The antioxidant protects tissues from damage and increases healing. It’s naturally made by muscles, but production is increased during cardiovascular exercise. The results of the findings were published in Redox Biology.
According to Yan’s analysis, even just one workout session can increase production of the antioxidant. So, he’s encouraging people to find a way to exercise while making sure to maintain social distancing.

“We cannot live in isolation forever,” he said. “Regular exercise has far more health benefits than we know. The protection against this severe respiratory disease condition is just one of the many examples.”

How diet impacts coronavirus risk

In addition to exercise, diet plays a key role in how our bodies respond to the coronavirus. We know that underlying conditions are what make so many people susceptible to COVID-19. Those with obesity, Type 2 diabetes, heart disease or high blood pressure are at the highest risk. Many of these conditions are impacted by diet.

But it’s not just making a few smart food choices once in a while. It’s a complete lifestyle change that can be affected by everything from where and how you live to culture, resources and habits.

“Healthy living is very difficult for Americans facing relentless advertising for processed and unhealthy foods, addictive (salt and sugar) ultra-processed food, entrenched and culturally-reinforced taste preferences, limited access to healthy foods for many Americans, public policy that subsidizes disease-promoting foods, sedentary behavior, and a health care and medical education system that still largely emphasizes sick care over prevention,” writes Casey Means, M.D., a practicing physician with a clinical focus on nutrition, nutrigenomics and disease prevention, and Grady Means, a writer and former corporate strategy consultant, in The Hill.

Poor diet is “now the leading cause of poor health in the U.S.,” Dr. Dariush Mozaffarian, dean of the Freidman School of Nutrition Science and Policy at Tufts University, told Jane E. Brody of The New York Times. Fewer than one American adult in five is metabolically healthy, he said.

“Only 12 percent of Americans are without high blood pressure, high cholesterol, diabetes or pre-diabetes,” he said. “The statistics are horrifying, but unlike COVID they happened gradually enough that people just shrugged their shoulders. However, beyond age, these are the biggest risk factors for illness and death from COVID-19.”

Metabolic syndrome is a cluster of conditions including high blood pressure, high blood glucose, poor cholesterol, high triglycerides and excess abdominal fat, according to the American Heart Association. Metabolic health and the immune system influence each other. When the former is lacking, infections can increase.

Many people are turning to unhealthy comfort foods during this crisis. Others are limited in what they can find because of empty store shelves. But the biggest problem is those who live in food deserts and poor communities that never had access to healthy foods in the first place.

“The COVID pandemic has cast a glaring light on longstanding costly and life-threatening inequities in American society. Those living in economically challenged communities, and especially people of color, are bearing the heaviest burden of COVID-19 infections. But while diet-related disorders increase vulnerability to the virus, limited national attention has been paid to lack of access to nutritionally wholesome foods that can sustain metabolic health and support a vigorous immune system,” Brody writes.

“Clearly, when this pandemic subsides, a lot more attention to the American diet will be needed to ward off future medical, economic and social calamities from whatever pathogen next comes down the pike.”

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Regular Exercise Helps Patients Combat Cancer


OUTRUNNING CANCER: Tumors on the lungs of sedentary mice (left) and animals that ran on wheels (right) after injection with melanoma cells.
L. PEDERSEN ET AL., CELL METAB, 2016

Bente Klarlund Pedersen

Mathilde was diagnosed with breast cancer at the age of 44. Doctors treated her with surgery, chemotherapy, and radiation, and Mathilde’s physician informed her that, among many other side effects of her cancer treatment, she could expect to lose muscle mass. To fight muscle wasting, Mathilde began the intensive physical training program offered to cancer patients at the Rigshospitalet University Hospital of Copenhagen. The program consists of 3.5-hour sessions of combined resistance and aerobic training, four times a week for six weeks. Although the chemotherapy made her tired, Mathilde (a friend of mine, not pictured, who requested I use her first name only) did not miss a single training session.

“In a way it felt counterintuitive to do intensive, hard training, while I was tired and nauseous, but I was convinced that the training was good for my physical and mental health and general wellbeing,” Mathilde told me in Danish. She followed the chemo- and radiotherapy strictly according to the prescribed schedule. She was not hospitalized, acquired no infections, and did not develop lymphedema, a failure of the lymphatic system that commonly occurs following breast cancer surgery and leads to swelling of the limbs.

Physical exercise is increasingly being integrated into the care of cancer patients such as Mathilde, and for good reason. Evidence is accumulating that exercise improves the wellbeing of these patients by combating the physical and mental deterioration that often occur during anticancer treatments. Most remarkably, we are beginning to understand that exercise can directly or indirectly fight the cancer itself.

An increasing amount of epidemiological literature strongly indicates that exercise training may lower the risk of cancer, control disease progression, amplify the effects of anticancer therapy, and improve physical function and psychosocial outcomes. For example, a 2016 study of more than 1.4 million individuals in the US and Europe found that people could reduce their cancer risk with moderate to vigorous leisure-time exercise training. The phenomenon held across several different cancers, including breast, colon, rectum, esophagus, lung, liver, kidney, bladder, and head and neck. And the combined results of approximately 700 unique exercise intervention trials, involving more than 50,000 cancer patients in total, leave little doubt that patients benefit from physical activity, showing improvements such as reduced toxicity of anticancer treatment, decreased disease progression, and enhanced survival. The same studies showed that exercise training improves mood, decreases loss of muscle mass, and helps cancer patients return to work earlier after successful treatment. Some studies show that 150 minutes per week of moderate exercise nearly double the chance of survival compared with breast cancer patients who don’t exercise during treatment.

Hundreds of animal studies, conducted over decades, suggest that the link is likely causal: in mice and rats, exercise leads to a reduction in the incidence, growth rate, and metastatic potential of cancer across a large variety of models of different human and murine tumor types. But how exercise helps fight cancer is a bit of a black box. Exercise may improve the efficacy of anticancer treatment by boosting the immune system and thereby attenuating the toxicity of chemotherapy and immunotherapy. Cancer patients are also likely to benefit from the overall health-promoting properties of physical activity, such as improved metabolism and enhanced cardiovascular function.

Uncovering the mechanisms whereby exercise induces anticancer effects is crucial to fighting the disease. Exercise-related factors that have a direct or indirect anticancer effect could serve as valuable biomarkers for monitoring the amount, intensity, and type of exercise required to best aid cancer treatment. Such research could also potentially highlight novel therapeutic targets.

Each workout matters

Regardless of the nature of the training, the primary setting of exercise’s effect on cancer is the bloodstream. Long-term training has been associated with a reduction in the blood levels of systemic risk factors, such as sex hormones, insulin, and inflammatory molecules. However, this effect is only seen if exercise training is accompanied by weight loss, and researchers have not yet established causal direct links between regular exercise training and the reductions in the basal levels of these risk factors. Alternatively, the anticancer effect of exercise could also be the result of something that occurs within individual sessions of exercise, during which muscles are known to release spikes of various hormones and other factors into the blood.

To learn more about the effects of individual bouts of exercise versus long-term training regimens, Christine Dethlefsen, a graduate student in my laboratory, incubated breast cancer cells with serum obtained from cancer survivors at rest before and after a six-month training intervention that began after patients completed primary surgery, chemotherapy, and radiotherapy. For comparison, she incubated other cells with serum obtained from blood drawn from these patients immediately after a two-hour acute exercise session during their weeks-long course of chemotherapy. Her study revealed that serum obtained following an exercise session reduced the viability of the cultured breast cancer cells, while serum drawn at rest following six months of training had no effect.

These data suggest that cancer-fighting effects are driven by repeated acute exercise, and each bout matters. In Dethlefsen’s study, incubation with serum obtained after a single bout of exercise (consisting of 30 minutes of warm-up, 60 minutes of resistance training, and a 30-minute high-intensity interval spinning session) reduced breast cancer cell viability by only 10 to 15 percent compared with control cells incubated with serum obtained at rest. But a reduction in tumor cell viability by 10 to 15 percent several times a week may add up to clinically significant inhibition of tumor growth. Indeed, in a separate study, my colleagues and I found that daily, voluntary wheel running in mice inhibits tumor progression across a range of tumor models and anatomical locations, typically by more than 50 percent.

Exercise’s molecular messengers

One prime candidate for helping to explain the link between exercise and anticancer effects is a group of peptides known as myokines, which are produced and released by muscle cells. Several myokines are released only during exercise, and some researchers have proposed that these exercise-dependent myokines contribute to the myriad beneficial effects of physical activity for all individuals, not just cancer patients, perhaps by mediating crosstalk between the muscles and other parts of the body, including the liver, bones, fat, and brain.

Exercise’s Anticancer Mechanisms

Researchers are beginning to understand that not only can exercise improve cancer patients’ overall wellbeing during treatment, but it may also fight the cancer itself. Experiments on cultured cells and in mice hint at some of the mechanisms that may be involved in these direct and indirect effects.

1) Exercising muscles release multiple compounds known as myokines. Several of these have been shown to affect cancer cell proliferation in culture, and some, including interleukin-6, slow tumor growth in mice.

2) Exercise stimulates an increase in levels of the stress hormones epinephrine and norepinephrine, which can both act directly on tumors and stimulate immune cells to enter the bloodstream.

3) Epinephrine also stimulates natural killer cells to enter circulation.

4) In mice, interleukin-6 appears to direct natural killer cells to home in on tumors.

5) In lab-grown cells and in mice, epinephrine, norepinephrine, and some myokines hinder tumor growth and metastasis.

The best-characterized myokine is interleukin-6, levels of which increase exponentially during exercise in humans. At least in mice, interleukin-6 is involved in directing natural killer (NK) cells to tumor sites. But there are approximately 20 known exercise-induced myokines, and the list continues to grow. Preliminary studies show that myokines can reduce cancer growth in cell culture and in mice. For example, when treated with irisin, a myokine best known for its ability to convert white fat into brown fat, cultured breast cancer cells were more likely to lose viability and undergo apoptosis than were control cells. A study I led found that oncostatin M, another myokine that is upregulated in murine muscles after exercise, also inhibits breast cancer proliferation in vitro. And a team led by Toshikazu Yoshikawa of Kyoto Prefectural University determined that in a mouse model of colon cancer, a myokine known as secreted protein acidic and rich in cysteine (SPARC) reduced tumorigenesis in the colon of exercising mice. Overall, skeletal muscle cells may be secreting several hundred myokine types, but of these, only about 5 percent have been investigated for their biological effects. And researchers have tested fewer for whether they regulate cancer cell growth.

Not all of the molecular messengers released in response to exercise come from the muscles. Notably, exercise induces acute increases in epinephrine and norepinephrine, stress hormones released from the adrenal gland that are involved in recruiting NK cells in humans. Murine studies show that NK cells can signal directly to cancer cells. In Dethlefsen’s study, when breast cancer cells incubated with serum obtained after a bout of exercise were then injected into mice, they showed reduced tumor formation. The exercise-induced suppression of breast cancer cell viability and tumor formation were, however, completely blunted when we blockaded β-adrenergic signaling, the pathway through which epinephrine and norepinephrine work. These findings suggested that epinephrine and norepinephrine are responsible for the cancer-inhibiting effects we observed. Epinephrine and norepinephrine, which activate NK cells, have also been shown to act on cancer cells through the Hippo signaling pathway, which is known for regulating cell proliferation and apoptosis. Exercise-induced spikes in these stress hormones activate this pathway, which somehow inhibits the formation of new malignant tumors associated with metastatic processes.

Calling the immune system

In addition to acting directly on tumors, the myokines released during and after exercise are known to mobilize immune cells, particularly NK cells, which appear to be instrumental to the exercise-mediated control of tumor growth in mice.

The late molecular biologist Pernille Højman of the Centre for Physical Activity Research at Rigshospitalet was a leader in discerning this mechanism. In the study described above that compared tumor growth in active and sedentary mice, on which I was also an author, Højman looked more closely at the tumors and found that the running mice had twice as many cytotoxic T cells and five times more NK cells than those animals housed without a wheel.

Højman repeated the experiment on mice that had been engineered to lack cytotoxic T cells. Again, she found that mice with access to running wheels had smaller tumors. When she performed the same test on mice that had intact T cells but lacked NK cells, the tumors of all the mice grew to the same size. This suggested that the NK cells, and not the T cells, were the link between exercise and tumor growth suppression.

Work by other groups had demonstrated that epinephrine has the potential to mobilize NK cells, and Højman and the rest of our team wondered if epinephrine had a role in mediating the anticancer effects of exercise. We injected mice that had malignant melanoma with either epinephrine or saline and found that the hormone indeed reduced the growth of tumors, but to a lesser degree than what was observed in the mice that had access to a wheel. Something else had to be involved.


AND STAY OUT: Exercise activates natural killer cells (purple) and helps them home to tumors.

To find out what, our team tested the effects of interleukin-6, which we suspected was the additional exercise factor involved in tumor homing of immune cells. When we exposed inactive mice to both epinephrine and interleukin-6, the rodents’ immune systems attacked the tumors as effectively as if the animals had been running.

While much remains to be learned about how physical exercise influences cancer, evidence shows that exercise training is safe and feasible for patients with the disease and contributes to their physical and psychosocial health. (See “Exercise and Depression” on page 44.) Being active may even delay disease progression and improve survival. A growing number of patients, including Mathilde, are undergoing exercise training to fight physical deterioration during cancer treatment. As they do so, scientists are working hard to understand the pathways by which physical activity results in anticancer activity.

Exercise and Depression

Depression is a severe adverse effect of cancer and cancer therapy. The risk of depression can be as high as 50 percent for some cancer diagnoses, although this number varies a great deal depending on cancer type and stage (J Natl Cancer Inst Monogr, 32:57–71, 2004). In addition to its effects on a patient’s quality of life, depression can hinder compliance with treatment, and it’s a risk factor for mortality in cancer patients (Lancet, 356:1326–27, 2000). In recent years, healthcare providers have increasingly integrated physical exercise into the care of cancer patients with the aim of controlling disease and lessening treatment-related side effects, while researchers have amassed evidence supporting the assertion that such training can lower symptoms of depression in these patients (Acta Oncol, 58:579–87, 2019). The biological mechanisms behind this beneficial effect remain to be determined, although some clues have emerged.

For example, a study in mice found that exercise-dependent changes in metabolism result in reduced accumulation of some neurotoxic products (Cell, 159:33-45, 2014). In cancer patients, systemic levels of kynurenine, a neurotoxic metabolite associated with fatigue and depression, are upregulated (Cancer, 121:2129-36, 2015). In mice, exercise enhances the expression of the enzyme kynurenine aminotransferase, which converts kynurenine into neuroprotective kynurenic acid, thereby reducing depression-like symptoms.

Findings such as these, together with exercise’s well-documented effects in alleviating depression among patients without cancer, suggest that incorporating exercise into cancer treatment may benefit mental as well as physical health.

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Exercising Before Eating Burns More Fat

Exercising before breakfast may have more health benefits than waiting until after the meal to get moving, according to a study published in the Journal of Clinical Endocrinology & Metabolism in October.

Researchers led by Javier Gonzalez, a physiologist at the University of Bath in England, conducted the study on a group of 30 overweight, sedentary men. One group drank a carbohydrate-laden vanilla shake for breakfast two hours before moderate cycling, while another group drank it after the same exercise. Both groups exercised three times per week. A third group was given the carb-rich drink but did not work out.

While riders in both cycling groups burned about the same number of calories each time they exercised, those in the group that worked out before drinking the shake burned about twice as many calories from fat per ride as the ones who had the shake beforehand. After the six-week study, members of the exercise-before-meal group also had improved insulin sensitivity, which lowers the risk of diabetes. People in both exercise groups had improved cardiorespiratory fitness compared to those who did not cycle, according to the study.

Exercising before breakfast may have burned more fat because fatty acids can fuel cells if glucose isn’t available, such as after a time of fasting when blood sugar is low, according to Runner’s World. While exercising before breakfast takes advantage of overnight fasting, similar results might be possible by abstaining from food at another time. “We believe that the key is the fasting period, rather than the time of day,” Gonzalez tells The New York Times.

Emily Makowski is an intern at The Scientist. Email her at emakowski@the-scientist.com.

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Life-long strategies that may help decrease the risk of developing dementia

There are no instant, miracle cures. But recent studies suggest we have more control over our cognitive health than we might think. It just takes some effort.

When it comes to battling dementia, the unfortunate news is this: Medications have proven ineffective at curing or stopping the disease and its most common form, Alzheimer’s disease. But that isn’t the end of the story. According to a recent wave of scientific studies, we have more control over our cognitive health than is commonly known. We just have to take certain steps—ideally, early and often—to live a healthier lifestyle.

In fact, according to a recent report commissioned by the Lancet, a medical journal, around 35% of dementia cases might be prevented if people do things including exercising and engaging in cognitively stimulating activities. “When people ask me how to prevent dementia, they often want a simple answer, such as vitamins, dietary supplements or the latest hyped idea,” says Eric Larson, a physician at Kaiser Permanente in Seattle and one of a group of scientists who helped prepare the report. “I tell them they can take many common-sense actions that promote health throughout life.”

The Lancet report, distilling the findings of hundreds of studies, identifies several factors that likely contribute to dementia risk, many of which can be within people’s power to control. These include midlife obesity, physical inactivity, high blood pressure, Type 2 diabetes, social isolation and low education levels.

Of course, there are no guarantees. Dementia is a complicated disease that has multiple causes and risk factors, some of which remain unknown. Nevertheless, there is increasing evidence that people—even those who inherit genes that put them at greater risk of developing Alzheimer’s in later life—can improve their chances by adopting lifestyle changes.

“It’s not just about running three times a week,” says Sarah Lenz Lock, executive director of AARP’s Global Council on Brain Health. “Instead, it’s about a package of behaviors, including aerobic exercise, strength training, a healthy diet, sleep and cognitive training.”

Because most neurodegenerative diseases take years, if not decades, to develop, researchers say the best time to focus on brain health is long before symptoms occur—ideally by midlife if not before. Still, they emphasize that it is never too late to start.

What follows is a look at what scientific studies tell us about possible ways to reduce dementia risk.

1. Blood-pressure control

The potential role that cardiovascular health—including blood pressure—plays in dementia has been one of the tantalizing highlights of recent research based on the Framingham Heart Study, which has followed thousands of residents of Framingham, Mass., and their relatives since 1948.

The research found a 44% decline in the dementia rate among people age 60 or older for the period 2004 to 2008, compared with 1977 to 1983. Diagnoses fell to two for every 100 study participants from 3.6 in the earlier period. Over the same roughly 30 years, the average age at which dementia was diagnosed rose to 85 from 80.

Co-author Claudia Satizabal, an assistant professor at UT Health San Antonio, says the research suggests that improvements in cardiovascular health and education levels help explain the trend. Improvements in dementia rates have occurred only in participants “who had at least a high-school diploma,” the study says. And as dementia rates have fallen, the study also says, so have the rates of “stroke and other cardiovascular diseases,” thanks in part to a greater use of blood-pressure medication.

Unlike studies in which participants are randomly assigned to different treatment groups and then monitored for results, the Framingham study and others that analyze population data cannot definitively prove a cause-and-effect relationship. Dr. Satizabal says that while the significant decline in dementia rates since 1977 suggests that management of stroke and heart issues could have contributed, that “is something that needs more research.”

A recent study that randomly assigned participants to different treatment goals offers further evidence for the idea that high blood pressure is a treatable risk factor that leads to dementia.

In 2010, researchers at Wake Forest School of Medicine began enrolling almost 9,400 people age 50 and older with high blood pressure in one of two groups. With the aid of medication, one group reduced its systolic blood pressure—which measures pressure in the arteries when the heart contracts—to less than 120. The other group aimed for less than 140.

The group with lower blood pressures experienced such significantly lower rates of death, strokes and heart attacks that in 2015 the researchers stopped the trial ahead of schedule. The scientists concluded it would be unethical to continue because most people should be targeting the lower blood pressure, says the study’s co-author Jeff Williamson, a Wake Forest medical school professor.

In 2017 and 2018, the researchers performed a final round of cognitive tests on participants and discovered that the lower-blood-pressure group had 19% fewer diagnoses of mild cognitive impairment, often a precursor to dementia, and 15% fewer cases of any type of dementia, mild or otherwise.

Using MRIs, the researchers scanned 673 participants’ brains and, upon follow-up, found less damaging changes in the lower-blood-pressure group.

“This is the first trial that has demonstrated an effective strategy for prevention of cognitive impairment,” says Kristine Yaffe, professor of psychiatry, neurology and epidemiology at the University of California, San Francisco. “That’s pretty big news,” says Dr. Yaffe, who wasn’t involved in the study.

2. Exercise

Several studies that have followed large numbers of people for years suggest that physically active individuals are less likely than inactive peers are to develop dementia, according to a recent World Health Organization report.

Exercise increases the flow of blood to the brain, improves the health of blood vessels and raises the level of HDL cholesterol, which together help protect against cardiovascular disease and dementia, says Laura Baker, a professor at Wake Forest School of Medicine. Exercise can also lead to the formation of new brain synapses and protect brain cells from dying.

Prof. Baker’s studies suggest that aerobic exercise can help improve cognitive function in people with mild memory, organizational and attention deficits, which are often the first symptoms of cognitive impairment.

One recent study conducted by Prof. Baker and several co-authors enrolled 65 sedentary adults ages 55 to 89 with mild memory problems. For six months, half completed four 60-minute aerobic-exercise sessions at the gym each week. Under a trainer’s supervision, they exercised mainly on treadmills at 70% to 80% of maximum heart rate. The other half did stretching exercises at 35% of maximum heart rate.

At the beginning and end of the study, researchers collected participants’ blood and spinal fluid and obtained MRI scans of their brains. Over the six months, the aerobic-exercise group had a statistically significant reduction in the level in their spinal fluid of tau protein, which accumulates in the brains of people with Alzheimer’s. They also had increased blood flow to areas of the brain that are important for attention and concentration, and their scores on cognitive tests improved. The stretching group, in contrast, showed no improvement on cognitive tests or tau levels.

3. Cognitive training

Many population studies suggest that education increases cognitive reserve, a term for the brain’s ability to compensate for neurological damage. The Framingham study, for example, found that participants with at least a high-school diploma benefited the most from declining dementia rates, compared with participants with less education.

In another population study, researchers at Columbia University analyzed data from 593 people age 60 or older, 106 of whom developed dementia. People with clerical, unskilled or semiskilled jobs had greater risk of getting the disease than managers and professionals.

In a separate study, some of the same researchers followed 1,772 people age 65 or older, 207 of whom developed dementia. After adjusting the results for age, ethnic group, education and occupation, the authors found that people who engaged in more than six activities a month—including hobbies, reading, visiting friends, walking, volunteering and attending religious services—had a 38% lower rate of developing dementia than people who did fewer activities.

In yet another study, researchers at institutions including Rush University Medical Center’s Rush Institute for Healthy Aging examined the brains of 130 deceased people who had undergone cognitive evaluations when alive. Among individuals in whom similar levels of Alzheimer’s-related brain changes were seen in the postmortem examinations, the researchers found that those who had more education generally had shown higher cognitive function.

Yaakov Stern, a professor at Columbia University College of Physicians and Surgeons who has written about these studies and the impact of education on dementia, recommends maintaining “educational and mentally stimulating activities throughout life.” This fosters growth of new neurons and may slow the rate at which certain regions of the brain shrink with age. It also promotes cognitive reserve, he says.

4. Diet

Efforts to study the impact of diet on dementia are relatively new, but there are some indications that certain diets may be beneficial in lowering the risk of dementia.

Several population studies, for instance, suggest that people with a Mediterranean diet, which is high in fish, fruits, nuts and vegetables, have lower rates of dementia, according to the World Health Organization.

But a variation on that diet may offer even more protection against the development of Alzheimer’s disease, according to a study released in 2015.

In this study, researchers including Dr. Martha Clare Morris, director of the Rush Institute for Healthy Aging, analyzed data from 923 people ages 58 to 98 who kept detailed food diaries about what they ate from 2004 to 2013.

In total, 158 subjects developed dementia. But among individuals who remained cognitively healthy, a high proportion had consumed a diet heavy in leafy green and other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil and wine (in moderation). Their diets were limited in red meat, butter, cheese, sweets and fried and fast foods.

This diet, which researchers named the Mind diet, shares many elements of a Mediterranean diet. But the Mind diet prescribes more foods—including berries and leafy green vegetables—that are associated with lower rates of neurological diseases.

The researchers scored each of the 923 participants on how closely their detailed eating habits followed three diets: Mind, Mediterranean, and Dash diet, designed to reduce high blood pressure. For each diet, researchers ranked the participants based on their scores, subdividing them by the degree to which they followed each diet—closely, partly or little.

This led to several discoveries: First, there were about 50% fewer Alzheimer’s diagnoses among participants who most closely followed either the Mind diet or the Mediterranean diet, compared with those who followed either diet only a little. For the Dash diet, there was a 39% reduction for those who were most faithful to its rules.

Meanwhile, even those who only partly followed the Mind diet saw a 35% reduction in Alzheimer’s diagnoses, while no reduction was seen for those who only partly followed either the Mediterranean or Dash diet.

In contrast to the Mediterranean and Dash diets, “even modest adherence to the Mind diet may have substantial benefits for prevention of Alzheimer’s disease,” says Kristin Gustashaw, a dietitian at Rush.

5. Sleep

No one knows for sure why we sleep. One theory is that sleep helps us remember important information by performing a critical housekeeping function on brain synapses, including eliminating some connections and strengthening others.

Another theory is that sleep washes “toxic substances out of our brains that shouldn’t be there,” including beta amyloid and tau proteins that are implicated in Alzheimer’s, says Ruth Benca, a professor of medicine at the University of California, Irvine.

In a 2015 study, Prof. Benca and others examined 98 participants without dementia ages 50 to 73. Many were at genetic risk for the disease. Brain scans revealed that those reporting more sleep problems had higher levels of amyloid deposits in areas of the brain typically affected by Alzheimer’s.

“Poor sleep may be a risk factor for Alzheimer’s,” says Prof. Benca, who is conducting a study to see whether treating sleep problems may help prevent dementia.

She says sleep—or a lack of it—may help explain why about two-thirds of Alzheimer’s patients are women. Some researchers theorize that during menopause women can become vulnerable to the disease, in part due to increased prevalence of insomnia.

6. Combination

There is a growing consensus that when it comes to preserving brain health, the more healthy habits you adopt, the better.

According to a forthcoming study of 2,765 older adults by researchers at Rush, nonsmokers who stuck to the Mind diet, got regular exercise, engaged in cognitively stimulating activities and drank alcohol in moderation had 60% fewer cases of dementia over six years than people with just one such habit.

A study published in July found that people at greater genetic risk for Alzheimer’s appear to benefit just as much from eating well, exercising and drinking moderately as those who followed the same habits but weren’t at elevated genetic risk for the disease.

The study, by researchers including Kenneth Langa, associate director of the Institute of Gerontology at the University of Michigan, examined data from 196,383 Britons age 60 and older. Over about a decade, there were 38% fewer dementia diagnoses among individuals who had healthy habits and a gene, APOE4, that puts people at higher risk for Alzheimer’s, than there were among people who had the gene and poor habits. The gene increases the risk for Alzheimer’s by two to 12 times, depending on how many copies a person has.

Among participants with low genetic risk for Alzheimer’s, healthy habits were associated with a 40% reduction in the incidence of the disease. The results suggest a correlation between lifestyle, genetic risk and dementia, the study says.

Many point to a recent clinical trial in Finland of 1,260 adults ages 60 to 77 as proof that a multipronged approach can work.

The researchers, from institutions including the Karolinska Institute in Sweden and the National Institute for Health and Welfare in Helsinki, randomly assigned half of the participants, all deemed at high risk for dementia, to regular sessions with nutritionists, exercise trainers and instructors in computerized brain-training programs. The participants attended social events and were closely monitored for conditions including high blood pressure, excess abdominal weight and high blood sugar.

“They got support from each other to make lifestyle changes,” says co-author Miia Kivipelto, a professor at the Karolinska Institute in Sweden.

The other half received only general health advice.

After two years, both groups showed improvements in cognitive performance. But the overall scores of the intensive-treatment group improved by 25% more than the scores for the other group. The intensive-treatment group scored between 40% and 150% better on tests of executive function, mental speed and complex memory tasks, suggesting that a multifaceted approach can “improve or maintain cognitive functioning in at-risk elderly people,” the study says.

“We are studying whether exercise and lifestyle can be medicine to protect brain health as we get older,” says Prof. Baker, who is overseeing a U.S. study modeled on the Finnish trial.

https://apple.news/AzlC5CLNvQJWJrsP-qrJFIw

Carissa Liebowitz on how running, and physical challenge in general, expands our comfort zone to share ourselves with others.


Carissa Liebowitz (at right, in the purple shirt)

‘Running is a safe space… we can scrape the barrel of our souls and go back to our regular lives without repercussion.’

If left to our own devices with free time and adequate resources, what would we choose to do?

While in Nepal recently, en route to reach the starting line of the Everest Marathon, I found such happiness in trekking daily, falling asleep at 7:30 p.m., and no agenda other than to take in the beautiful scenery and move my body.

It helped, of course, to be led by someone else. To not have to give any thoughts about where I was going, how I was going to find food or shelter, or what I needed to do to prepare for the next day.

But if I shake away the potential complications, I am left with how I like living. Using my body for moderate work pretty much all day with periods of adequate rest, time for reflection, minimal internet connectivity, and at peace.

I think about the things that some people would find moderately uncomfortable and those are the things I enthusiastically embraced. Crawling into my sleeping bag with a layer of dust. Surprise meals prepared in a traditional way. Rest days with light hiking.

In much of the first world, we have evolved to live in a 72° environment with infrequent activity. Our biggest challenges are keeping our inboxes clear and deciding what’s for dinner.

I like the idea of hiking for a long period of time. As a sense of accomplishment, yes, but also, as a sense of being in nature for extended periods of time. And of course, the reality of not dealing with the day-to-day is ultimately appealing. No bills, no housework and no commuting.

I wonder about the lack of communication if I were solo. I came to truly enjoy the camaraderie of breaking bread or unpacking a life story during a shared experience.

Snippets of dark life moments came out and these are the kind of things that you trust to people that you share a close and physical experience with. I heard more recently that these are evolutionary behaviors — the strenuousness of the physical breaks down the filters of social norms.

When we sit in a comfortable space without struggle, our inclination is to hide these things away. Even in our close friendship circles or family, our darker secrets are not shared. Perhaps because of the fragility of the relationship?

But if there is nothing to lose, it becomes easy to unload the burdens on a stranger. Our relationship could be nothing at best and that wouldn’t change the state of affairs. But it could strengthen our bond and push us to outcomes we’ve only dreamed of.

Friendships forged over miles of running are built on the same foundation. The higher the level of suffering, the more it seems we are willing to open up and offer the true versions of ourselves.

I’ve found that I’m the most authentic version of myself in the midst of a long training run or deep into a tough race. The things I might caution myself from sharing with a non-running friend over coffee suddenly fall easily out of my mouth when my legs are tired and my heart rate is high.

While running, I might be more apt to open up about my struggles with my husband’s multiple sclerosis battle or share my very undecided thoughts on spirituality.

I’ll give you all the details about my eating disorder in high school and losing my job, 15 years into my career. Running is my safe space. There is an unspoken notion that we can scrape the barrel of our souls and go back to our regular lives without repercussion.

It’s not just me either. The skeletons (and treasures!) slip out of my running friends’ closets too. Many of them I know on a more personal level after just a few runs than some friends I’ve known half of their lifetimes.

As we dig a little deeper physically, we dig a little deeper psychologically and in the discomfort of our bodies, we somehow find our comfort zone.

https://halfmarathons.substack.com/p/carissa-liebowitz-on-how-running?token=eyJ1c2VyX2lkIjozNzY4NzIsInBvc3RfaWQiOjE3MjE1NSwiXyI6InVnNEVTIiwiaWF0IjoxNTc0MDAwMDEyLCJleHAiOjE1NzQwMDM2MTIsImlzcyI6InB1Yi0xMzczIiwic3ViIjoicG9zdC1yZWFjdGlvbiJ9.K0w17guN-6eemVW90j3BDXEIef7AHDveH6OOzqgxsGw

Any amount of running can lower a person’s risk of early death, an analysis of multiple studies finds.

By Jonathan Lambert

If you’re looking for motivation to take up running, perhaps this will help. A new study finds that people who run as little as once a week have a lower risk of early death compared with people who don’t run at all.

In fact, any amount of running was associated with a 27 percent lower risk of premature death. And researchers found no evidence that running more alters that number significantly, according to a new meta-analysis published November 4 in the British Journal of Sports Medicine.

“This is good news for the many adults who find it hard to find time for exercise,” says Elaine Murtagh, an exercise physiologist at Mary Immaculate College in Limerick, Ireland, who was not involved in the study. “Any amount of running is better than none.”

While this conclusion might seem obvious to runners, the science has been fairly mixed, says public health researcher Željko Pedišić of Victoria University in Melbourne, Australia. “Some studies found a significant benefit of running, but others did not,” he says.

Also unclear was whether the duration or intensity of running mattered. Researchers who study the effects of running think about the activity in terms of doses, as though it were itself a medicine. Pedišić says that while it might make sense that more running would yield greater health benefits, some studies have sparked debate by suggesting that higher levels of running — more than 250 minutes a week — could actually negate any benefits in terms of mortality.

Pedišić and his colleagues tried to make sense of these conflicting findings by pooling and reanalyzing data from previous studies, an approach known as a meta-analysis. They settled on 14 previously published studies, which collectively asked 232,149 participants about their running habits and then tracked their health over a period of time from 5 ½ to 35 years.

Over the course of each study a total of 25,951 participants died, allowing the researchers to look for statistical associations between running and risk of death.

The researchers found that runners, even those who reported running as infrequently as once a month, had a 27 percent reduced risk of death from any cause compared with non-runners. Each study differed slightly in how they defined a runner, making it difficult to say exactly how little running is necessary for a benefit, though Pedišić says taking just a few strides a week is almost certainly not enough.

Still, the lower risk of early death was more or less the same across all running doses, from running no more than once a week for less than 50 minutes to running every day for a weekly total of 250 minutes. “All these doses of running are significantly associated with lower risk of death,” Pedišić says. “There was no significant difference between frequency, duration or pace,”

“Not finding a trend does not mean that the trend does not exist,” Pedišić cautions. A trend could be too small to be detected within the sample size. Studying the health effects of heavy running can be difficult because there aren’t many people who run that much, he says.

While more evidence is needed to determine if there is an upper limit to how much running is beneficial, this study fits with other research finding health benefits for any level of activity, says Angelique Brellenthin, a kinesiologist at Iowa State University in Ames who was not involved in the study, “Any amount of physical activity that you can fit into your schedule is good for you,” she says.

Running just once a week may help you outpace an early death

How Fast You Walk Might Show How Fast You’re Aging

By Dennis Thompson

Middle-aged folks who worry about healthy aging would do well to keep an eye on their walking speed.

Turns out that the walking speed of 45-year-olds is a pretty solid marker of how their brains and bodies are aging, a new study suggests.

Slow walkers appear to be aging more rapidly, said senior researcher Terrie Moffitt, a professor of psychology and neuroscience at Duke University. They’ve lost more brain volume in middle-age than folks with a quicker walking pace, and also perform worse on physical and mental tests, she said.

“For those people who were slow walkers for their age group, they already had many of the signs of failing health that are regularly tested in a geriatric clinic,” Moffitt said.

In the study, middle-aged people who walked slower than 3.6-feet per second ranked in the lowest fifth when it comes to walking speed, and those are the individuals already showing signs of rapid aging, said Dr. Stephanie Studenski, a geriatrician with the University of Pittsburgh School of Medicine.

“It takes many body systems to have you walk well,” Studenski said. “It takes a good heart, good lungs, good nervous system, good strength, good musculoskeletal system and a variety of other things. Gait speed summarizes the health of all of your body’s systems.”

Gait speed tests are a standard part of geriatric care, and are regularly given to people 65 and older, Moffitt said.

“The slower a person walks, that is a good predictor of impending mortality,” Moffitt said. “The slower they walk, the more likely they will pass away.”

Moffitt and her colleagues suspected that gait tests might be valuable given at an earlier age, figuring that walking speed could serve as an early indicator of how well middle-aged people are aging.

To test this notion, the researchers turned to a long-term study of nearly 1,000 people born in a single year in Dunedin, New Zealand. These people have been tested regularly since their birth in 1972-1973 regarding a wide variety of medical concerns.

This group of study participants recently turned 45, and as they did, the research team tested their walking speed by asking each to repeatedly amble down a 25-foot-long electronic pad, Moffitt said.

Each person walked down the pad at their normal rate, and then again as fast as they could. They also were asked to walk as fast as possible while reciting the alphabet backward, Moffitt said.

All of the participants then were subjected to a battery of aging tests normally used in geriatric clinics.

In addition, they underwent an MRI brain scan to test the volume of their brains, since a shrinking brain has been linked to dementia and Alzheimer’s disease.

The participants also were given a variety of mental and physical tests. The physical tests involved things like balancing on one foot, standing up out of a chair as fast as they could, or gripping a monitor as tightly as they could to test hand strength.

“All these things are very subtle,” Moffitt said. “They’re not anything that would knock you over with a feather. You have to test them in order to find them.”

The findings showed that people who were in the lowest fifth for walking speed had signs of premature and rapid aging.

Studenski said, “It’s the bottom 20% that’s by far in bigger trouble than the others.”

The slower walkers also looked older to a panel of eight screeners asked to guess each participant’s age from a facial photograph.

The findings were published online Oct. 11 in JAMA Network Open.

A gait test could be an easy and low-cost way for primary care doctors to test how well middle-aged patients are aging, said Studenski, who wrote an editorial accompanying the new study.

Doctors could place sensors at the beginning and end of a hallway, and test patients’ walking speed as they head down to the examination room, she added.

However, doctors would need to be taught how to interpret gait speed for middle-aged patients, the same way that geriatricians already are trained to interpret walking speed in seniors.

Middle-aged people with a slower gait could try to slow their aging by eating healthy, exercising, quitting smoking, and maintaining better control over risk factors like high blood pressure and elevated cholesterol, Studenski and Moffitt suggested.

An even better use of walking speed could be as an early test of drugs and therapies meant to counter dementia and other diseases of aging, Moffitt said.

These therapies usually are difficult to assess because researchers have to wait years for people to grow old and display the hoped-for benefits, she noted.

“They need something cheap and effective they can do now to evaluate these treatments,” Moffitt said. “If they give it to people and it speeds up their walking, we’ve really got something there.”

SOURCES: Terrie Moffitt, Ph.D., professor, psychology and neuroscience, Duke University, Durham, N.C.; Stephanie Studenski, M.D., MPH, geriatrician, University of Pittsburgh School of Medicine; Oct. 11, 2019, JAMA Network Open, online

https://consumer.healthday.com/senior-citizen-information-31/misc-aging-news-10/how-fast-you-walk-might-show-how-fast-you-re-aging-751167.html

These 6 Specific Exercises Can Cut Body Weight, Even if You’re Predisposed to Obesity

by DAVID NIELD

We know that a range of factors influence weight, including those related to lifestyle and genetics, but researchers have now identified six specific exercises that seem to offer the best chance of keeping your weight down – even if your genes don’t want you to.

Based on an analysis of 18,424 Han Chinese adults in Taiwan, aged between 30 and 70 years old, the best ways of reducing body mass index (BMI) in individuals predisposed to obesity are: regular jogging, mountain climbing, walking, power walking, dancing (to an “international standard”), and lengthy yoga practices.

But interestingly, many popular exercise types weren’t shown to do much good for those who’s genetic risk score makes them more likely to be obese.

Specifically, exercises including cycling, stretching, swimming and legendary console game Dance Dance Revolution don’t appear to be able to counteract genetic bias (though are beneficial in many other ways).

“Our findings show that the genetic effects on obesity measures can be decreased to various extents by performing different kinds of exercise,” write the researchers in their paper published in PLOS Genetics.

“The benefits of regular physical exercise are more impactful in subjects who are more predisposed to obesity.”

Besides BMI, the team also looked at four other obesity measures for a more complete picture: body fat percentage (BFP), waist circumference (WC), hip circumference (HC), and waist-to-hip ratio (WHR).

Regular jogging – 30 minutes, three times a week – turned out to be the most effective way of counteracting obesity genes across all of them.

The researchers also suggest, based on the information dug up in the Taiwan BioBank database, that the less effective forms of exercise typically don’t use up as much energy, which is why they don’t work quite so well.

The researchers specifically noted that activities in cold water, such as swimming, could make people hungrier and cause them to eat more.

The study was able to succeed in one of its main aims, which was to show that having a genetic disposition towards obesity doesn’t mean that obesity is inevitable – the right type of exercise, carried out regularly, can fight back against that built-in genetic coding.

“Obesity is caused by genetics, lifestyle factors, and the interplay between them,” epidemiologist Wan-Yu Lin, from the National Taiwan University, told Newsweek. “While hereditary materials are inborn, lifestyle factors can be determined by oneself.”

It’s worth noting that not every type of exercise was popular enough within the sample population to be included: activities like weight training, table tennis, badminton or basketball may or may not be helpful, too. There wasn’t enough data to assess.

But with obesity numbers rising sharply across the world – and 13 percent of the global population now thought to quality as being obese – it’s clear that measures need to be taken to reverse the trend.

Being obese affects our physiological health in the way it increases the risk of cardiovascular disease, some cancers, and other issues; and there’s evidence that being seriously overweight can have a negative effect on our brains too.

Studies like this latest one can point towards ways of sticking at a healthy weight, even when the genetic cards are stacked against it. In some cases all it takes is a few minutes of exertion per day.

“Previous studies have found that performing regular physical exercise could blunt the genetic effects on BMI,” conclude the researchers.

“However, few studies have investigated BFP or measures of central obesity. These obesity measures are even more relevant to health than BMI.”

The research has been published in PLOS Genetics.

https://www.sciencealert.com/these-six-exercises-can-keep-weight-down-even-with-genetic-tendencies-for-obesity

The truth about exercise and weight loss

by MARY JO DILONARDO

When you want to lose weight, there are two things you do: eat less and exercise more.

Just cutting calories should cause you to drop pounds. But exercise alone is rarely enough for weight loss. Life isn’t fair, after all.

Think of it this way: When going on a 30-minute brisk walk at about 4 miles per hours (that’s a 15-minute mile), a 155-pound person burns about 167 calories, according to Harvard Medical School. Want to celebrate your accomplishment? That exercise is quickly erased by a large scoop of vanilla ice cream or two small chocolate chip cookies.

If more serious exercise is your thing, 30 minutes of vigorous stationary bicycling burns 391 calories. But that gets wiped away with one slice of pepperoni pizza.

It doesn’t seem fair how all that effort can be nullified by a few bites of tasty food.

Is more exercise the answer?

It seems like simple math: If exercising for x minutes burns y calories, then just exercise longer and burn more calories. But research shows it’s not that easy.

Recently, New Scientist explained it with a story called, “Why doing more exercise won’t help you burn more calories.” Science writer Teal Burrell explored the idea of the so-called exercise paradox. People who dramatically increase their workout regimens often find that despite all the sweat and motion, they shed few pounds. Scientists have several theories why that might happen.

They eat more. You went for a grueling hike and are so proud of yourself, so you reward yourself later with a chocolate shake. People tend to overestimate the calories they burn when they exercise. In one study, people worked out on a treadmill and then were told to eat from a buffet the amount of food that equaled the calories they thought they burned. They guessed they had burned about 800 calories and ate about 550, when they had really burned just 200.

They move less. You went on that grueling hike in the morning, so you sprawled on the couch the rest of the day. Another theory is that people make up for their workouts by spending the rest of the time being sedentary. These are called “compensatory behaviors” when the moving and not moving balance each other out. But exercise physiologist Lara Dugas of Loyola University doesn’t buy this idea. “That doesn’t mean you lose that 500-calorie run because you’re sedentary for the rest of the day,” she tells New Scientist. “That doesn’t make sense.”

The body adapts. The theory that seems to make the most sense is that when you exercise more, your body adjusts by spending less energy on internal functions, from the immune system to digestion. Those systems that are working in the background, spending calories, just become more efficient when you exercise more, researchers think.

The role of exercise

Mathematician and obesity researcher Kevin Hall explained to Vox why adding more exercise probably won’t lead to much weight loss. Hall used the National Institutes of Health’s Body Weight Planner to calculate that if a 200-pound man added 60 minutes of medium-intensity running four days per week for a month while keeping his calorie intake the same, he’d lose five pounds. “If this person decided to increase food intake or relax more to recover from the added exercise, then even less weight would be lost,” Hall added.

So if someone is trying to lose a lot of weight, it would take a lot of time and effort to try to lose pounds based on exercise alone.

But of course, that doesn’t mean you should cancel your gym membership and toss your sneakers into the back of your closet. Exercise is still a key part of the one-two punch to weight loss. You just have to combine it with calorie control.

Nutritionists will say that weight loss is about 80% diet and 20% exercise. So yes, watch the brownies and the snacks if you’re trying to lose the love handles, but keep moving. It’s an eat-move combination that does require smart eating and regular movement to be healthy.

https://www.mnn.com/health/fitness-well-being/stories/why-exercise-doesnt-matter-all-much-weight-loss?utm_source=Weekly+Newsletter&utm_campaign=10b270682b-RSS_EMAIL_CAMPAIGN_FRI0802_2019&utm_medium=email&utm_term=0_fcbff2e256-10b270682b-40844241

Why exercise won’t make you lose weight

By Ben Tinker

There’s no shortage of things people swore to leave behind in 2018: bad jobs, bad relationships, bad habits. But chances are, you’re beginning 2019 with something you didn’t intend: a few extra pounds.

Every January, one of the top New Year’s resolutions is to lose weight. And if you’re looking to be successful, there’s something you should know: Diet is far more important than exercise — by a long shot.

“It couldn’t be more true,” nutritionist and CNN contributor Lisa Drayer said. “Basically, what I always tell people is, what you omit from your diet is so much more important than how much you exercise.”

Think of it like this: All of your “calories in” come from the food you eat and the beverages you drink, but only a portion of your “calories out” are lost through exercise.

According to Alexxai Kravitz, an investigator at the National Institute of Diabetes and Digestive and Kidney Diseases — part of the National Institutes of Health, “it’s generally accepted that there are three main components to energy expenditure”:

(1) Basal metabolic rate, the amount of energy it takes just to keep your body running (blood pumping, lungs breathing, brain functioning)

(2) Breaking down food, scientifically referred to as “diet-induced thermogenesis,” “specific dynamic action” or the “thermic effect of food”

(3) Physical activity

For most people, basal metabolic rate accounts for 60% to 80% of total energy expenditure, Kravitz said. He cited a study that defines this as “the minimal rate of energy expenditure compatible with life.” As you get older, your rate goes down, but increasing your muscle mass makes it go up.

About 10% of your calories are burned digesting the food you eat, which means roughly 10% to 30% are lost through physical activity.

“An important distinction here is that this number includes all physical activity: walking around, typing, fidgeting and formal exercise,” Kravitz said. “So if the total energy expenditure from physical activity is 10% to 30%, exercise is a subset of that number.

“The average person — professional athletes excluded — burns 5% to 15% of their daily calories through exercise,” he said. “It’s not nothing, but it’s not nearly equal to food intake, which accounts for 100% of the energy intake of the body.”

What’s more, as anyone who’s worked out a day in their life can tell you, exercising ramps up appetite — and that can sabotage even the best of intentions.

According to calculations by Harvard Medical School, a 185-pound person burns 200 calories in 30 minutes of walking at 4 miles per hour (a pace of 15 minutes per mile). You could easily undo all that hard work by eating four chocolate chip cookies, 1½ scoops of ice cream or less than two glasses of wine.

Even a vigorous cycling class, which can burn more than 700 calories, can be completely canceled out with just a few mixed drinks or a piece of cake.

“It’s so disproportionate — the amount of time that you would need to [exercise] to burn off those few bites of food,” Drayer said.

The sentiment here is that you’ve “earned” what you eat after working out, when instead — if your goal is to lose weight — you’d be better off not working out and simply eating less.

Of course, not all calories are created equal, but for simplicity’s sake, 3,500 calories equal 1 pound of fat. So to lose 1 pound a week, you should aim to cut 500 calories every day. If you drink soda, cutting that out of your diet is one of the easiest ways to get there.

“The other thing is that exercise can increase your appetite, especially with prolonged endurance exercise or with weight lifting,” Drayer said. “It’s another reason why I tell people who want to lose weight to really just focus on diet first.”

It is cliché — but also true — that slow and steady wins the race when it comes to weight loss. According to the US Centers for Disease Control and Prevention, “evidence shows that people who lose weight gradually (about 1 to 2 pounds per week) are more successful at keeping weight off.”

“All this is not to say that exercise doesn’t have its place,” Drayer said. “It’s certainly important for building strength and muscle mass and flexibility. It can help to manage diseases, including heart disease and diabetes. It can improve your mood. It can help fight depression. But although exercise can help with weight loss, diet is a much more important lifestyle factor.”

As the saying goes: Abs are made in the kitchen, not the gym.

https://www.cnn.com/2019/01/04/health/diet-exercise-weight-loss/index.html